Capacitors have functions for controlling electrical current and voltage in electronic circuits, or function as secondary batteries, and are therefore used in many kinds of electronic equipment.
Multilayer ceramic capacitors, film capacitors, aluminum electrolytic capacitors, and tantalum capacitors can be given as examples of capacitors.
Of these types of capacitors, multilayer ceramic capacitors have both smaller sizes and higher electrostatic capacitances than other capacitors. Therefore, demand for multilayer ceramic capacitors continues to increase for use in small-sized electronic equipment such as mobile telephones.
FIG. 9A is a perspective view schematically illustrating a typical multilayer ceramic capacitor, FIG. 9B is a cross-sectional view taken from a line A-A in FIG. 9A, and FIG. 9C is a cross-sectional view taken from a line B-B in FIG. 9A.
A multilayer ceramic capacitor 100 is constituted of a capacitor body 101 and external electrodes 103 provided on both end portions of the capacitor body 101. The multilayer ceramic capacitor will be referred to simply as a “capacitor” hereinafter.
The capacitor body 101 includes a dielectric body 109 constituted of ceramic layers 105 and internal-electrode layers 107 laminated in an alternating manner, and a cover portion 111 provided around the periphery of the dielectric body 109.
Upon a voltage being applied to the capacitor, an electrostrictive effect arises in a lamination direction in which the dielectric body 109 extends. However, at this time, the electrostrictive effect does not arise in the cover portion 111 provided in the periphery of the dielectric body 109. Distortion thus arises between the dielectric body 109 and the cover portion 111, which can lead to delamination at parts within the cover portion 111 where the distortion is concentrated (see Patent Document 1, for example).